Streetsweeper vacuum pickup head assembly



April 8, 1969 s. TAMNY STREETSWEEPER VACUUM PICKUP HEAD ASSEMBLY Filed July 27, 1967 Sheet I of 5 5/Mo/v IZMNY flrromlews- April 8, 1969 s. TAMNY STREETSWEEPER VACUUM PICKUP HEAD ASSEMBLY 5 M W 2 Tm m M w m m April 8, 1969 s TAMNY STREETSWEEPER VACUUM PICKUP HEAD ASSEMBLY Sheet Filed July 27. 1967 I N VENTOR.

5/440 TZMNY A ril 8, 1%9

S. TA MNY STREETSWEEPER VACUUM PICKUP HEAD ASSEMBLY Sheet S/MQN ZZM/vs Filed July 27, 1967 April 8, 1969 s. TAMNY 3,436,783

STREETSWEEPER VACUUM PICKUP HEAD ASSEMBLY Filed July 27. 1967 Sheet 5 of 5 United States Patent US. Cl. 15-340 17 Claims ABSTRACT OF THE DISCLOSURE The invention pertains to a vacuum debris pickup head assembly carried by and forwardly of a streetsweeper vehicle, the assembly comprising a pair of peripherally intermeshed gutter brooms, and a hood carrying the brooms and having depending sides forwardly and rearwardly of the outer broom peripheries positionable in close proximity to a road surface being swept. The brooms operate to receive between the-m debris which is displaced to a suction duct at the rear of the hood. Main features of the head assembly are: (l) mounting of the brooms to the hood structure for independent relative vertical and tilting movements; (2) mounting of the hood assembly to the vehicle for lateral swinging movements and effecting such movements by mechanism operating to elevate the hood from outward sweeping position to automatically established centered traveling position and to return the hood, upon lowering, to such outward sweeping position; (3) maintaining yielding resistance to inward impact displacement of the hood; (4) provision of a form of suction duct capable of free flow of swept debris out of the hood; and (5) a secondary suction chamber and duct arrangement in association with convergent rear walls of the hood.

INTRODUCTORY AND ILLUSTRATIVE EMBODI- MENT DESCRIPTION OF THE INVENTION While suction or vacuum-type streetsweepers, as generally characterized, are known, the present invention relates to a particular type of gutter broom sweeping and suction removal of the swept debris.

In its general aspects, the invention provides improvements in a vacuum pickup head assembly carried by and forwardly of a streetsweeper vehicle, and comprising a pair of gutter brooms shiftable transversely to sweeping positions selectively at opposite street curbs, the brooms being contained within a hood depending close to the street surface and to which suction is communicated in a manner to displace debris swept inwardly and between the brooms into an external receiver. The hood may be shaped to have depending aprons or sides forwardly of the brooms and extending convergently and rearwardly to a suction location from which the swept debris is taken out of the hood.

Particularly contemplated is an arrangement wherein the gutter brooms are in peripheral intermeshing contact so as to have disintegrating action on the debris being swept inwardly between the brooms and thus reduce some debris sizes for non-clogging reception within the suction system.

The invention has for one of its objects mounting of the gutter brooms for lifting and lowering movements within and relative to the hood, so that in an outwardly displaced position of the hood the brooms may be lowered within the hood to independent resiliently supported ground contact, and elevated in the hood when the latter is restored to a centered traveling position. Particularly contemplated is a broom elevator whereby the broom automatically lowers and raises within the hood coincidentally and respectively with outward lowering and inward raising bodily movements of the hood.

Concerning the hood control the invention provides a mounting means and mechanism which operates automatically in response to elevation of the hood from an outward sweeping position to a predetermined traveling position centered relative to the sweeper vehicle, and operating upon lowering of the hood to return it to the outward sweeping position. Included also in the hood mounting and control is means for yieldably cushioning inward displacement of the hood from sweeping position as by curb impact.

Other features and objects of the invention have to do with the suction system. One departure from conventional suction ducts is the use of an elliptical suction conduit leading from the convergence of the rearward hood sides, the elliptical configuration presenting by comparison with a circular duct of the same area, an enlarged (elongated) dimension capable of passing correspondingly enlarged pieces of debris.

Also contemplated in the suction arrangement is a spaced arrangement of rear convergent sides of the hood to provide suction chambers to receive finer debris passing beneath the inner walls, these chambers preferably having suction connections independent of or in addition to the main suction duct.

All the features of the invention as well as the details of an illustrative embodiment will be more fully understood from the following description of the accompanying drawings, in which:

FIG. 1 is a plan view showing the mounted hood and gutter broom assembly with a portion of the hood broken away to expose one of the gutter broom mountings;

FIG. 2 is a longitudinal section taken on line 22 of FIG. 1 showing the hood and broom assembly in lowered sweeping position;

FIG. 3 is a cross section as viewed from line 3-3 of FIG. 2;

FIG. 4 is an enlarged cross section on line 4-4 of FIG. 2;

FIG. 5 is a view similar to FIG. 2 showing the hood and broom assembly in elevated traveling position;

FIG. 6 is a fragmentary enlargement of the left hand extent of FIG. 4 showing the parts in changed position;

FIG. 7 is an enlarged fragmentary section on line 77 of FIG. 3;

FIG. 8 is an elevation as viewed from line 88 of of FIG. 7;

FIG. 9 is an enlarged fragmentary section on line 9-9 of FIG. 2; and

FIG. 10 is a fragmentary enlarged section on line 10-10 of FIG. 1.

DESCRIPTION OF THE PREFERRED EMBODIMENT The hood and broom assembly as shown in FIG. 1 comprises generally a pair of gutter brooms 10, which may be of conventional form and construction, positioned forwardly of a sweeper vehicle having a front frame member 11, the brooms being contained within a suction generally indicated at 12, for lifting, lowering and lateral shifting movements therewith as will appear. As illustrated the brooms project outwardly from the sides of the hood at 13 to be able to sweep curbed gutters at either side of the street without interference by the hood. Centrally inside the hood the brooms peripherally overlap at 10a by intermeshing of their bristles, a relation that remains in all shifted positions of the hood and brush assembly. An object and advantage of so intermeshing the brooms is to achieve a disintegrating action on debris being swept inwardly by and between the brooms in the directions of the arrows, thus to reduce debris particle sizes entering the suction system at the rear of the hood.

The hood and broom assembly is supported by suspension from a cantilever beam 14 formed of a top 15, sides 16 and a rear bottom extention 17. The beam is mounted for lateral swinging by pivot rod 18 extending through the flanges 19 of a bracket 20 welded to the front face of the frame member 11. A coil spring 21 is mounted for lateral over-center displacement at opposite sides of the hood and vehicle frame axis 22 centered in the hood position of FIG. 1, by anchoring the forward end of the spring to the top 15 of the beam at 22, and attaching the rear terminal of the spring 23 to the pivoted connection of arm 24 carried by pivot 18, and piston 25 operating within cylinder 26. By appropriate controls the piston 25 may be actuated to throw the spring to either side of the pivot 18, in which positions the spring yieldably urges the hood and broom assembly to one or the other of the outward sweeping positions at which the spring serves also to cushion the assembly against lateral impact as against a curb.

The hood 12 is formed as a shell having a forward horizontal top extent 28 and a rear continuance 29 slop ing down to an end 30, see FIG. 9, containing the suction conduit 31. The shell includes front side 32, generally parallel lateral sides 33 which continue convergently at 34 to the end 30. Internally the shell has a transverse wall 35 continuing horizontally and rearwardly at 36 to a hollow beam 37 projecting transversely beyond the convergent sides of the shell and attached to casters 38 which zupport the hood in sweeping position on the road surace.

The forward side 32 of the shell carries a flexible extension or apron 40 depending in close proximity to the street surface 41 in the FIG. 2 sweeping position, the convergent sides 34 carrying similar flexible aprons 42 having such proximity to the street surface that together the front and converging aprons afford such enclosure forwardly and rearwardly of the brooms as to permit induction of air flow from about the brooms into the hood and maintenance of high velocity air flow therein into the suction conduit 31. The latter may have any suitable flexible conduit connection, not shown, with a conventional suction blower and debris receptacle caried by the sweeper vehicle. The convergent sides 34 of the hood may also mount, see FIG. 10, as by attachment to supports 43 by bolts 44, a pair of inner flexible aprons 45 spaced coextensively from aprons 42 to form chambers 46 which receive finer debris particles passing through the greater street surface clearance at 47 beneath aprons 45. Preferably, suction is communicated to chambers 46 independently of the main suction duct 31 as by way of conduits 48 which also connect with the sweeper suction blower and debris collection system.

As particularly illustrated in FIG. 9, the main suction conduit 31 is elliptical in cross section with the long axis of the ellipse substantially horizontal. By this configuration the duct is enabled to receive and pass larger pieces of debris through the long dimension than could be received by a circular conduit of corresponding area.

Reference previously has been made to the effect of the broom intermesh at 10a to have a disruptive action on disintegrable debris pieces, thus tending to reduce their size for rearward sweep in the hood and entry into the suction duct.

Individually the brooms 10 are mounted to be variably positionable within the hood 12 by a parallel linkage arrangement comprising an upper plate 50 the side flanges 51 of which are pivoted at 52 to bracket plates 53, and a pair of lower arms 54 pivoted to the brackets at 55. At their opposite extremities the plate 50 and arms 54 are pivoted at 56 and 57 to the flange 58 of a transverse plate 59 to the inside of which is mounted bracket 60 which supports the conventional rotary, e.g. hydraulic, motor drive 61 for the broom 10. The ground pressure of the broom as viewed in FIG. 2 is variable in its lowered resiliently supported position by adjustment at 61 of coil spring 62 connected at 63 to one of the arms 54.

Raising and lowering of the hood and broom assembly as well as effecting its lateral movements to either sweeping position from a centered elevated traveling position, are accomplished and controlled by an over-center mechanism generally indicated at 64. This mechanism comprises a bell crank type lever 65 pivoted to the beam 14 and 66 and pivoted also at 67 to the piston of cylinder 68, the opposite terminal of which is pivotally supported at 69 by the beam. On the pivot 69 is carried a sheave 70 about which passes cable 71 connected at 72 to the lever 65 and attached at its opposite end to arm 73 secured to shaft 75 carried by flanges 76 fixed to the top 28 of the hood shell. The shaft carries fixed arms 74 pivoted at 77 to lift rods 78 extending downwardly through openings in the hood and plate 50 to terminals 79 having in the FIG. 2 sweeping position of the assembly sufiicient clearance below plate 50 to allow for varying the brush ground pressure by adjustment of spring 62.

Referring particularly to FIGS. 4 and 6, the sweeper frame bracket 19 carries a horizontal cam plate 81 containing slot 82 the cam edges 83 of which converge forwardly to reduced spacing at 84 which is centered with the longitudinal axes of the hood in its centered traveling position of FIG. 1. Slot 82 receives the follower terminal 85 of rod 86 pivotally received at 87 within the lever 65.

The hood and broom assembly 12 is variably suspended by parallel linkage arrangement comprising a forward link 88 pivotally carried at 89 by the terminals of the pivot shaft 69, the sides 90 of the link converging to a pivotal connection at 91 with the hood flanges 76. Similarly, a second parallel link 92 pivoted to the beam carried trunnions 93 extends forwardly and convergently at 94 to pivot about beam 95 extending between the flanges 76.

In the traveling position of the hood assembly as illustrated in FIG. 5, cylinder 68 will have been actuated by suitable remote control, not shown, to rotate lever 65 about shaft 66 to bring cable 71 above and in overcenter relation to the shaft, which relation tends to retain the hood assembly in elevated traveling position. In this position the hood 12 is elevated by the cable transmitted lift applied to arm 74 and lift rod 78, the latter also acting to elevate the broom 10 within the hood shell as illustrated in that elevation of the lift rod engages terminal 79 first with plate 50 to swing it upwardly against the hood, see FIG. 5, following which the hood elevates to the traveling position. In this same position the cam rod 86 is pulled forwardly to bring its follower 85 into the reduced extent 92 of the cam slot, which defines and maintains the transversely centered position of the hood assembly. In effect the hood is thus locked in that position against the pull of the over center spring 21.

In the operation of lowering the hood assembly to sweeping position which is determined toward curbs at either the right or left of the sweeper by throwing spring 21 as previously described, cylinder 68 is actuated to swing lever 65 down to the FIG. 2 position, as a consequence of which the cam follower 85 is backed into the wide convergent extent 82 of the cam slot as shown in FIG. 4, and cable 71 is lowered about the sheave 70 to drop the hood and lower the broom to sweeping position therein by release of lifting force applied to the linkage 51, 54. The sweeping position of the hood assembly in lowered sweeping condition is established by the engagement of casters 38 with the road surface.

The described mechanisms automatically restore the hood assembly upon elevation from the FIG. 2 condition, to the FIG. 1 centered alinement with the carrier sweeper. After being brought to one side or other of the convergent cam slot 82 for sweeping position, upon elevation follower 85 is progressively cammed forwardly into the fixed alinement of the reduced extent 92, thus causing the beam 14 and the entire hood assembly to restore to corresponding alinement as illustrated in FIG. 6.

Provision may be made for adjusting the tilt angle of each broom in the plane of FIG. 8, as by pivoting the mounting bracket 60 at 100 to plate 69 so that by adjustment of nut 101 on bolt 102 terminating at 103 in the bracket, the tilt angle of the latter and therefore of the broom may be varied. The broom is held in adjusted position by the tightening elfect of bolt 104 extending through the plate slot 105 into the bracket, which effect may be had by using a spring washer self axially tightening bolt. The pivot bolt 100 may be of the same known type.

By reason of the low position and remoteness of the broom tilt axis from the location of the broom intermesh at a, the brooms will retain their intermeshing relation at all adjusted positions.

I claim:

1. A vacuum pickup head assembly carried by and forwardly of a streetsweeper vehicle, comprising a pair of circular brooms driven for rotation about generally vertical axes and positioned in peripherally intermeshing relation centrally of said assembly to receive between them debris swept inwardly by the brooms, a suction hood overlying the brooms and having depending sides forwardly and rearwardly of the brooms and having their bottom edges positionable proximate to a road surface being swept by the brooms, a debris suction duct com-. municating with the interior of the hood rearwardly of the brooms, means mounting the hood for elevation and movement with the brooms transversely of the vehicle to outward sweeping positions, and means mounting the brooms to the hood for independent movement relative thereto.

2. The assembly of claim 1, including resilient means for variably restraining movement of the brooms relative to the hood to vary the broom ground pressure.

3. The assembly of claim 1, in which said broom mounting means operates to maintain said peripherally intermeshed relation of the brooms when they are relatively moved.

4. The assembly of claim 1, including means for variably tilting the brooms and in which said broom mounting and tilting means operate to maintain said peripherally intermeshed relation of the brooms when they are both relatively tilted and relatively vertically moved.

5. The assembly of claim 1, including means yieldably resisting inward impact displacement of the hood from said outward sweeping positions.

6. The assembly of claim 1, in which said hood mounting means includes means automatically responsive to elevation of the hood from an outward sweeping position to return the hood to a predetermined position centered relative to the sweeper vehicle.

7. The assembly of claim 1, including also means associated with said mounting means and responsive to elevation of the hood to elevate the brooms Within and relative to the hood.

8. A vacuum pickup head assembly carried by and forwardly of a streetsweeper vehicle comprising a pair of circular brooms driven for rotation about generally vertical axes and positioned in peripherally intermeshing relation centrally of said assembly to receive between them debris swept inwardly by the brooms, a suction hood overlying the brooms and having depending sides forwardly and rearwardly of the brooms and having their bottom edges positionable proximate to a road surface being swept by the brooms, a debris suction duct communicating with the interior of the hood rearwardly of the brooms, means mounting the hood for elevation and movement with the brooms transversely of the vehicle to outward sweeping positions, said mounting means including means automatically responsive to elevation of the hood from an outward sweeping position to a predetermined traveling position centered relative to the sweeper vehicle and operating upon lowering of the hood to return it to said outward sweeping position.

9. The assembly of claim 8, including means yieldably resisting inward impact displacement of the hood from said outward position.

10. The assembly of claim 8, in which the hood is pivoted for lateral swinging movement about a center fixed in relation to the sweeper vehicle.

11. The assembly of claim 8, in which said mounting means includes an over-center mechanism operating to re leasably maintain the hood in elevated position.

12. The assembly of claim 10, in which said mounting means includes an over-center mechanism operating to releasably maintain the head in elevated position.

13. A vacuum pickup head assembly carried by and forwardly of a streetsweeper vehicle, comprising a pair of circular brooms driven for rotation about generally vertical axes and positioned in peripherally intermeshing relation centrally of said assembly to receive between them debris swept inwardly by the brooms, a suction hood overlying the brooms and having depending sides forwardly and rearwardly of the brooms and having their bottom edges positionable proximate to a road surface being swept by the brooms, a debris suction duct communicating with the interior of the hood rearwardly of the brooms, means mounting the hood for elevation and movement with the brooms transversely of the vehicle to outward sweeping positions, the rearward sides of the hood converging to a suction location, and an internally unobstructed open suction tube leading from said location.

14. The assembly of claim 13, in which said tube is essentially elliptical in cross section.

15. The assembly of claim 13, in which the hood includes internal walls spaced from and generally paralleling said convergent sides of the hood toward said suction location to form chambers receptive of debris, and means communicating suction to said chambers.

16. The assembly of claim 15, in which the last mentioned means includes suction ducts communicating with said chambers independently of said suction tube.

17. The assembly of claim 13, including means providing ground support for the hood beneath said rearward convergent sides.

References Cited UNITED STATES PATENTS 1,546,441 7/1925 Prayer 15-340 X 3,186,021 6/1965 Krier et al. 15340 3,277,511 10/1966 Little et al 15340 X ROBERT W. MICHELL, Primary Examiner.

US. Cl. X.R. 15-87, 385 

